The problem with this is primarily that windows uses NTFS as it’s filesystem. Being proprietary, NTFS has never played well with Linux and installing it to an NTFS partition is regarded as a genuinely terrible idea. Converting partitions safely is nearly impossible to do in place.
I would like to point out that actors are usually contractually obligated to maintain a specific appearance. Stamos may literally have not been able to shave his head in solidarity, so while seemingly noncommittal I think there could be more to the gesture. As you say, Dave is the only authority on the matter either way.